CVE-2021-1871: Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerability

Published Jan 26, 2021
·
Updated

A flaw was found in WebKitGTK.

Impact: A remote attacker may be able to cause arbitrary code execution. Description: A logic issue was addressed with improved restrictions.

Reference: https://webkitgtk.org/security/WSA-2021-0003.html

Other sources

A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Apple iOS, iPadOS, and macOS WebKit contain an unspecified logic vulnerability that allows a remote attacker to execute code. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.

— CISA

WebKit. A logic issue was addressed with improved restrictions.

Credit

an anonymous researcher

Affected Software

19 affected componentsFixes available
debian/webkit2gtk
2.36.4-1~deb10u12.38.6-0+deb10u12.40.5-1~deb11u12.42.1-1~deb11u22.40.5-1~deb12u12.42.1-1~deb12u12.42.1-2
debian/wpewebkit
2.38.6-1~deb11u12.38.6-12.42.1-1
Apple macOS Big Sur<11.2
11.2
Apple Catalina
Apple Mojave
Apple iOS, iPadOS, and macOS
Apple Ipad Os<14.4
Apple iPhone OS<14.4
Apple iOS and macOS>=10.15<10.15.7
Apple iOS and macOS=10.15.7
Apple iOS and macOS=10.15.7-security_update_2020
Apple iOS and macOS=10.15.7-supplemental_update
Apple macOS>=11.0.1<11.2
Debian Debian Linux=10.0
Fedoraproject Fedora=33
Apple iOS<14.4
14.4
Apple iPadOS<14.4
14.4
Apple iPadOS<14.4
redhat/webkitgtk<2.32.0
2.32.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.36.4-1~deb10u1Fixed in 2.38.6-0+deb10u1Fixed in 2.40.5-1~deb11u1Fixed in 2.42.1-1~deb11u2Fixed in 2.40.5-1~deb12u1Fixed in 2.42.1-1~deb12u1Fixed in 2.42.1-2
  2. Upgrade

    Upgrade debian/wpewebkit to a version that resolves this vulnerability.

    Fixed in 2.38.6-1~deb11u1Fixed in 2.38.6-1Fixed in 2.42.1-1
  3. Upgrade

    Upgrade Apple macOS to a version that resolves this vulnerability.

    Fixed in 11.2
  4. Upgrade

    Upgrade Apple iOS and iPadOS to a version that resolves this vulnerability.

    Fixed in 14.4
  5. Upgrade

    Upgrade Apple iOS, iPadOS, and macOS to a version that resolves this vulnerability.

    Fixed in 14.4
  6. Upgrade

    Upgrade redhat/webkitgtk to a version that resolves this vulnerability.

    Fixed in 2.32.0
  7. Upgrade

    Upgrade macOS Catalina to a version that resolves this vulnerability.

    Patch Security Update 2021-001
  8. Upgrade

    Upgrade macOS Mojave to a version that resolves this vulnerability.

    Patch Security Update 2021-001
  9. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.36.4-1~deb10u1
  10. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.38.6-0+deb10u1
  11. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.40.5-1~deb11u1
  12. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.42.1-1~deb11u2
  13. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.40.5-1~deb12u1
  14. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.42.1-1~deb12u1
  15. Upgrade

    Upgrade debian/webkit2gtk to a version that resolves this vulnerability.

    Fixed in 2.42.1-2
  16. Upgrade

    Upgrade debian/wpewebkit to a version that resolves this vulnerability.

    Fixed in 2.38.6-1~deb11u1
  17. Upgrade

    Upgrade debian/wpewebkit to a version that resolves this vulnerability.

    Fixed in 2.38.6-1
  18. Upgrade

    Upgrade debian/wpewebkit to a version that resolves this vulnerability.

    Fixed in 2.42.1-1

Event History

Mar 30, 2021
Data Sourced
via Red Hat·08:07 PM
DescriptionSeverityAffected Software
Apr 2, 2021
CVE Published
via MITRE·06:06 PM
Data Sourced
via MITRE·06:06 PM
DescriptionWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2021-1871.

2

What is the title of this vulnerability?

The title of this vulnerability is Apple iOS iPadOS and macOS Remote Code Execution Vulnerability.

3

Which software is affected by this vulnerability?

Apple iOS, iPadOS, and macOS are affected by this vulnerability.

4

How can a remote attacker exploit this vulnerability?

A remote attacker can exploit this vulnerability to execute code.

5

Where can I find more information about this vulnerability?

More information about this vulnerability can be found on the Apple support website: [link](https://support.apple.com/en-us/HT212147) and [link](https://support.apple.com/en-us/HT212146).

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